Pilot valve or master control valve



xpriil 15, i924. Lf-MOSS@ H. W. BRADEN PILOT VALVE OR MASTER CONTROL VALVE Filed March 27, 1922 Patented Apr. l5, 1924.

Y Maase@ HENRY'W BRADEN, OF'LOS ANGELES, CALIFORNIA, @SSIG-'NOR, BY'VIYESNE ASSIGN- MENTS; OE ONE-'HALF TO 4R: L'. HAYES.

To'aZZ w/mwm'tmay/conceive Bc iti-known tliat-/IyHnNR-r 1V. BRADEN, ay citizen of the United. States, residing' in the-,city and county oftLos-Angeles. State of California, Ahave :invented aV -new and useful Pilot Valve on Master Control Valve,v

saidnpatenn butL-the-.objject for 'which-it isv intendedaisin generalfthe. same as-that of the pilot-valveeof.saidpatent.

Thegain: inV simplicityv obtained by= the present invention is such that l am able to dispense with anumberof the-.parts shown in. said patent.

Another advantage isf the addition cfa manual `control. tof the automatic control shownin said patent.

Other-. advantages withy respect toV simplicity of constr-u'ctionand ehcie'ncyof operation -wvill-apjiiearA fromy they following description-and ythe accompanying drawings forming a part lot the specification.

Referring to-said dra-wings, ITigure. 1 is avertical section on. line m1=m1 oiFi-g. 2.

Fig.l 2.- is a transverse section `online w24-af? of Fig; 1.

Fig. 3 is an enlarged sectional Ydetail'of an adjusting spring and parts adjacent thereto as seen in the upper left-hand-v portion of Fig. 2.` Y

Referring in detail tothe drawings, the pilot valve proper. comprises a. mainy cylinder 1V having ay wall. 2; extending diametrically otsaid. cylinder to divide the-same into twofchambers, a -chamben 3 which is the pistoni chamber piepen-and an intermediate chamber 4f. there-v being also` `an adjusting` chamber '4a. Within the piston chamber 3 isa piston havinga rod v6ertending sliding'ly through-'said wall-2. Said rod 6 has aV reducediportion or s-tem.7,eX- tending throughV the end wall Sat the end of intermediatey chamber 4 which is farthest from thepiston proper. rOutside ofV said lWall Slisthe adjusting: chamber 4a already referred". to communication vbetween said clianb`ers14e1and 'Llb'eing through a valve .passage 10-around stem 7. The shoulder 11 yof. piston rod' G'formsa yclosure to control communication through saidv vpassage 10. `When said shoulder -11 isY seated toy close passage -10,l `piston 5 `is preferably about onefourth ot an inch from wall 2.

Within chamberv el@ Ais an t adjusting spring 12 operating at oneend as `best shownfin Figg) against-a shouldered-collar 13 -which fits onfto `a smallprojection lll-on the end of the-stem 7 rIhe other end oit said spring 12l is mounted in asimilar mannerupon the inner end of an adustingv screw 15 ta ed into the outerA wall ofi the adjusting chamber 9.

The initial pressure- Venters the: piston chamben proper Sthrough conduits-flG-and 16a, andv an equal pressure from the same supply source (not shown)P is at all times lfurnished toI the 'adjusting` chamber 4a through conduit 17. Pet-cock 18 opens vent 182LA to atford relief; for' the pressure withiny the piston chamber proper, thereby preventing pressure from equalizing on opposite sidesfofthe piston y owing-to any leakage -therearound The exaust pipewlQ controlled: by valve 19@1 at. alltimes-aords relief; of: ythe pressure -wit'hin-k chamber 4?. Conduits-20 and 20a alfoid. communica-tion with the main cylinder 22. on opposite sidesfot-'thepiston 21 therein.

each end-7. the 'left-hand 'endso'fI said studs beingy tapped into theend of the left-hand member" 26. The two other members 255 and 25 slide-loosely over. said studs,1the cylinder head. 2.4Y being: held in place by nuts 28- screwingf onto the outer sends of Said studs.

Under` some conditions. it is desirable to manually operate the valvek controlled by the travel ofthe piston 5. Forthis purpose I provide an` operating` rod. 35 threaded through an internally threaded guide 36 within conduit 16, and provided With an operating handle 37. The inner end of said rod 35 operates against the outer side of the head ot piston 5 against the opposition of spring 12, said spring at all times holding said head aga-inst the end oit said rod. `By inserting guide 3G into the end of pipe 1G and having said rod extend axially through said pipe, a compact inexpensive construction is provided for the manually operable means. Said pipe 16 extends parallel to the direction of movement of piston In operation, the discharge valve 19a is set in a very slightly open position, and the adjusting screw 15 is regulated against the opposition of compression spring 12 in order to maintain the desired amount etopposition against the fluid pressure upon the right hand face (see Fig. 2) of the piston head 5. It, ior example, screw 15 is set at eighty pounds pressure, then a pressure of slightly over eighty pounds entering pipes 16, 1Gd Will move piston 5 and rod 6 toward the left, thus closing the annular passage 10. Vhen this occurs, the pressure against the end of the large piston 21, gradually Jfalls on account of leakage through pipe 20a, chamber 4 and pipe 19. rIhis causes the pressure arounf'd. piston 21 to move the same to the right, thus operating any desired balance valve (not shown). The pressure causing this last mentioned movement is supplied through pipes 20, chamber t and pressure supply pipe 17. Piston 21 will continue to move to the right until it reaches the limit of its travel, but will return to its initial position as soon as pressure in chamber 3 decreases enough to allow spring 12 to move rod 6 to the. right and 'reopen annular passage 10, causing pressure to equalize in both ends of cylinder 22, moving piston 21 to the left because of the area of its left face being less than that ot its right face.

I claim:

1. In a pilot valve, a cylinder, a wall to divide said cylinder into an end chamber and an intermedia-te chamber, a piston within said end chamber, an adjusting chamber in communication with said intermediate chamber, communication between said intermediate chamber and adjusting chamber being controlled by the movements of said piston, and a spring opposing said piston to determine the pressure required to open such communication,there being inlet and outlet ports to supply pressure to and relieve` pressure from said piston.

2. In a pilot valve, a cylinder, a Wall to divide said cylinder into an end chamber and an intermediate chamber', ai piston Within said end chamber, said piston having a rod extending movably through said Wall, a portion of said rod extending through the end of said cylinder farthest 'from the piston proper to constitute a valve at that point, an adjusting chamber in comn'iunication with said intermediate chamber through a passage controlled by said valve, and a spring opposing said piston to determine the pressure required to open said valve, there being inlet and outlet ports to supply pressure to and relieve pressure from said piston.

3. In a pilot valve, a cylinder, a wall extending diametrically of said cylinder to divide the same into an end chamber and an intermediate chamber, a piston Within said end chamber, said piston having a rod extending through said Wall, said rod having a reduced portion or stem extending vthrough the end of said cylinder farthest from the piston proper to constitute a valve at that point, an adjusting chamber in communication With the passage controlled by said valve, a spring operating against said piston rod to regulate the pressure to open said valve, means to regulate the tension of vsaid spring, there being a source of pressure supply to said adjusting chamber, outlet ports leading from said adjusting chamber and intermediate chamber and an eX- haust outlet from saidintermediate chamber.

1. In a pilot valve, a cylinder, a wall to divide said cylinder into an end chamber and an intermediate chamber, a piston Within said end chamber, an adjusting chamber in communication with said intermediate chamber, communication between said intermediate chamber and adjusting chamber being controlled by the movements of said piston, a spring opposing said piston to determine the pressure required to open such communication, there being inlet and outlet ports to supply pressure to and relieve pressure from said piston, and manually operable means to move said piston in opposition to said spring.

5. In a pilot valve, a cylinder, a Wall to divide said cylinder' into an end chamber and an intermediate chamber, a piston Within said end chamber, an adjusting chamber in communication with said intermediate chamber, communication between said intermediate chamber and adjusting chamber being controlled by the movements of said piston, a spring opposing said piston to determine the pressure required to openy such communication, there being inlet and outlet ports to supply pressure to and relieve pressure from said piston, an inlet pipe extending parallel to the direction oli 4movement of said piston, a rod extending axially of said inlet pipe, said rod having endivise engagement With said piston to move the same in opposition to said spring, and manually operable means to actuate said rod.

HENRY W. BRADEN'. 

